Activity Profile Differences Between Sub-Elite Futsal Teams

International Journal of Exercise Science 8(2) : 112-123, 2015. Whilst there are a range of studies examining the differences in match demands between levels of competition, there is an absence of the analysis these differences between teams within the same level of competition. The study used notational analysis to identify performance indicators that differentiated between sub-elite futsal teams from Brazil, Spain and Australia during regular season matches. Based on world rankings, Spanish and Brazilian futsal was deemed to be superior to Australian futsal. The Australian players spent a significantly greater time engaged in high intensity activity than the Spanish players (sprinting: 0.36% v. 0.06%, p\u3c0.05); running: 5.89% v. 3.33%). The Brazilian team displayed the greatest possession of the ball (40.0 ± 10.4%) when compared to the Spanish (23.5 ± 2.73%) and Australian teams (30.9 ± 2.54%) (p\u3c0.01). Additionally, the Brazilian and Spanish teams made a greater number of successful passes per minute of match-play than the Australian team (10.7 ± 1.06 v. 8.68 ± 0.81 v. 5.31 ± 0.60, respectively, p\u3c0.01). These results generally suggest that lower high intensity activity output and superior ball possession and passing accuracy appear to be critical determinants in discriminating between successful and unsuccessful match performance. Accordingly, training to improve technical and decision making skills, specifically related to maintaining ball possession and improving passing accuracy, will likely assist lower performing teams

INFLUENCE OF A SEASON OF ATHLETIC TRAINING ON LEG AND JOINT STIFFNESS IN HIGH LEVEL NETBALLERS

The purpose of this study was to ascertain the impact of a season of training on lower limb stiffness, joint stiffness and the contributing mechanisms during basic jumping and sports specific tasks. Eleven high level female netballers completed a maximal countermovement jump (basic), 50 m sprint and change of direction cutting task (sports specific) prior to and following a competition/training season. Student paired t-tests or their non-parametric equivalent identified no pre-post season stiffness changes, however stiffness mechanism changes during sports specific tasks did occur

Relationship of leg and joint stiffness during basic and sports specific tasks in high level athletes

The purpose of this study was to assess the stiffness relationship between basic jumping tasks and sports specific tasks, and the underlying joint stiffness contributions which contribute to leg stiffness modulation. Forty-seven high level female athletes from varying training backgrounds completed a maximal countermovement jump, drop jump, horizontal jump, 50 m sprint, change of direction cutting task and repetitive hopping. Pearson’s correlations or their non-parametric equivalent identified no relationship between basic jumping and sports specific tasks, however the repetitive hopping task exhibited a moderate relationship to each disciplines relevant sports specific task. Furthermore, joint stiffness contributions appeared to be unique to each athletic group. Results of this study appear to suggest sports specific tasks are superior screening tools for athletes

LOWER BODY STIFFNESS VARIATIONS AND ASSOCIATED INJURY RISK DURING SPORTS SPECIFIC TASKS

The purpose of this study was to evaluate the longitudinal stiffness changes and associated prospective lower limb injury risk across a season of training in female athletes. Thirty-nine high level female athletes from varied training backgrounds completed sports-specific tasks and repetitive hopping. Repeated measures analysis of variance, independent t-tests, receiver operating characteristics curves and logistic regression analysis were implemented to evaluate the identified aims of this study. Results suggest athletic training influences longitudinal changes in leg stiffness which may place athletes at increased injury risk. An optimal range of stiffness may exist allowing optimal performance and minimised injury risk

RELATIONSHIP OF LEG AND JOINT STIFFNESS DURING BASIC AND SPORTS SPECIFIC TASKS IN HIGH LEVEL ATHLETES

The purpose of this study was to assess the stiffness relationship between basic jumping tasks and sports specific tasks, and the underlying joint stiffness contributions which contribute to leg stiffness modulation. Forty-seven high level female athletes from varying training backgrounds completed a maximal countermovement jump, drop jump, horizontal jump, 50 m sprint, change of direction cutting task and repetitive hopping. Pearson’s correlations or their non-parametric equivalent identified no relationship between basic jumping and sports specific tasks, however the repetitive hopping task exhibited a moderate relationship to each disciplines relevant sports specific task. Furthermore, joint stiffness contributions appeared to be unique to each athletic group. Results of this study appear to suggest sports specific tasks are superior screening tools for athletes

The forest through the trees:Making sense of an ecological dynamics approach to measuring and developing collective behaviour in football

In this book, we interpret the literature that has analysed football performance from a tactical standpoint using an ecological dynamics perspective. This approach focuses on the performer–environment relationship and provides a basis for understanding the dynamic nature of performance in collective team sports (1) and will be explained in detail throughout. The first section of this text will provide a brief description of association football as well as commonly used methods to analyse football performance. The next section will briefly introduce common theories and practices used to measure team behaviour, decision-making, and performance enhancement in team sport, which are then used to introduce the ecological dynamics framework. This framework will then be used to aid the application of these findings for tactical analysis in team sports such as football. Finally, we will introduce some of the scientific literature on improving team performance, particularly in reference to team coordination and decision-making. The following sections of this book will deal specifically with how small-sided games can be used to develop tactical behaviour in football. A small-sided games approach was chosen as these modified games allow for the simultaneous development of players’ technical skills, conditioning, and ability to solve and overcome tactical challenges through coordinative behaviour and effective decision-making (2-5). Small-sided games provide an environment that mimics the perception–action couplings of in situ performance, which should, in theory, improve the transferability of learned behaviours to in-game performance (4, 6). As a result, small-sided games are often used by coaches and form an integral part of this text. Finally, we conclude with some recommendations for future research, and some practical considerations for coaches interested in applying the research discussed in this book

Effects of fatigue on muscle stiffness and intermittent sprinting during cycling

Purpose: It was recently demonstrated that musculoarticular (MA) stiffness is related to sprint cycling performance in nonfatigued conditions. This study examined whether relatively stiffer cyclists were more effective at sprinting under fatigued conditions, as occurs during endurance cycling competitions. Methods: MA stiffness of the quadriceps was assessed in 21 trained male cyclists (28.7 ± 9.5 yr, 1.74 ± 0.08 m, 67.5 ± 7.2 kg). Participants also performed a maximal 6-s sprint on a cycle ergometer to assess peak power output (PO peak ), peak crank torque (CT peak ), and peak rate of crank torque development (RCTD peak ). A cycling fatigue protocol then required cyclists to pedal at 30%, 35%, and 40% of PO peak and sprint at the end of each stage. Surface EMG was recorded from vastus lateralis during each sprint and analyzed in the time domain as integrated EMG (iEMG) and in the frequency domain as instantaneous median frequency (MDF) adopting a continuous wavelet transform. Participants were then retested for MA stiffness. Results: MA stiffness (-12%) was significantly reduced after the cycling protocol. Further, PO peak , CT peak , RCTD peak , and iEMG were reduced by 20%, 15%, 13%, and 20%, respectively, after the fatigue protocol (P < 0.05). When the cyclists were divided into relatively stiff (SG) and relatively compliant groups (CG), only SG exhibited significant decreases in MA stiffness, C T peak , RCTD peak (P < 0.05), and instantaneous MDF (R = 0.705). Conclusions: Whereas neuromechanical parameters were generally reduced under conditions of fatigue, stiff and compliant cyclists were affected differently, with the sprint abilities of SG decreased to the level of CG. It seems important for endurance cyclists to incorporate training strategies to maintain MA stiffness during competition to offset declines in sprint performance. © 2011 by the American College of Sports Medicine

The Effects of Respiratory-Muscle Training on Exercise in Older Women

This research examined the effects of respiratory-muscle (RM) training on RM function and exercise performance in older women. Twenty-six women (60-69 yr of age) were assessed for spirometry, RM strength (maximal inspiratory and expiratory pressure), inspiratory-muscle endurance, and walking performance to a perceived exertion rating of 'hard.' They were randomly allocated to a threshold RM training group (RMT) or a nonexercising control group (CON) for 8 wk. After training, the 22% (inspiratory) and 30% (expiratory) improvements in RM strength in the RMT group were significantly higher than in the CON group (

Differences in Lower-Body Stiffness Between Levels of Netball Competition

There are many notable differences in physical and skill attributes between competition levels, especially in team sports. Stiffness is an important mechanical factor to measure when considering athletic performance and injury incidence. Active vertical stiffness (Kvert) during hopping and passive stiffness during lying and standing were measured during the preseason period for 46 female netballers (24.0 6 3.7 years, 72.2 6 7.6 kg, 175.2 6 6.7 cm). Participants were classified as elite, sub-elite, representative or recreational based on their current level of competition. A 1-way analysis of variance revealed that elite players possessed significantly higher Kvert than recreational players (p = 0.018). Large effect sizes (ES) suggested that elite players also possessed higher Kvert than sub-elite (d = 1.11) and representative (d = 1.11) players. A number of large and moderate ES were also present when comparing the passive stiffness of elite players to their lower-ranked counterparts. The results of this study suggest that elite players possess higher levels of active stiffness when compared with their lower-ranked counterparts. The differences in stiffness levels may contribute to a player's ability to physically perform at an elite level and also provide one explanation into elevated rates of injury at higher levels of competition